Locking device fob zebo-setting mechanisms of calculating machines



Dec. 22 1925- 1,566,979

I O. P. SCHUMAN G MECHANISMS OF CALCULATING MACHINES LOCKING DEVICE FORZERO SETTIN Filed August 29, 1924 atented Dec. 22, 1925.

UNITED OTTO P. SCHUMAN, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR T0 RAPIDCAL- CULATOR COMPANY, OF PHILADELPHIA, PENNSYLVANIA.

LOCKING DEVICE FOR ZERO-SETTING MECHANISMS OF CALCULATING MACHINES.

'\ Application fllcd August 29, 1924. Serial No. 734,991.

To all whom it may concern:

Beit known that I, Or'ro P. SCHUMAN, a citizen of the United States,residing at Philadelphia, in the county of Philadelphia and State ofPennsylvania, have invented certain new and useful Improvements inLocking Devices for Zero-Setting Mechanisms of Calculating Machines, ofwhich the following is a specification.

The invention relates to calculating machines, and relates moreparticularly to look ing devices for zero setting mechanisms in theclass of calculating machines where the values of the calculations areset on setting disks having a variable number of teeth adapted totransmit the said values to a registering mechanism which is mounted ona slidable carriage ada ted to be shifted laterally along and para lelto the setting mechanism. The lateral shifting movement of the slidablecarriage enables the registering elements or numeral wheels which arecarried thereby, to be brought into cooperation with any of the settingdisks of the setting mechanism. The registering and revolution countingmechanisms of the carriage are provided' with any suitable zero-settingdevices which can be operated in any adjusted or displaced position ofthe carriage or of the setting mechanism.

It is well known that calculating machines of the character describedare likely to be damaged during the operation thereof, and especiallywhen the crank handle of the setting mechanism shaft is rotated when theshaft carrying the registering mechanism is not in its correct position.Furthermore, in machines of this character it is of importance that thenumeral wheels of the registering mechanism be returned to their zeroposition after each calculating operation, or otherwise a resetting ofthe setting mecha nism and subsequent operation of the crank handlewould render an incorrect or errone;- ous result on the registeringwheels.

The object of the present invention is to provide automatic, positiveand efliciently operating devices for securely locking the zero settingmechanism during operative ositions of the setting disks to preventundue damage to the machine, and further to prevent performance of thecalculating operation and consequent erroneous results when the numeralwheels of the registering mechanism have not been cleared or returned tozero position after the completion of aprovious calculating operation,

further object of the invention is to provide improved locking devicesof the character described, the automatic actuation of which positivelymaintains the setting wheels and disks in their adjusted position duringthe operation of the machine, thereby minimizing the possibility oferroneous results in the values of the calculations.

A further object of the invention is to provide locking devices for thezero setting mechanism of calculating machines, which, in addition tobeing positive and automatic in operation, are composed of few partswhich are economical to manufacture and A which are capable ofconvenient attachment to calculating machines of the class and characterdescribed.

ith such objects in view, as well as other advantages which may beincident to the use of the improvements, the invention consists in theparts and combinations thereof, hereinafter set forth and claimed, withthe understanding that the several necessary elements constituting thesame may be varied in proportions and arrangement without departing fromthe nature and scope of the invention. In order to make the inventionmore clearly understood there are shown in the accom-, panying drawingsmeans for carrying the same into practical efl'ect, without limiting theimprovements, instheir useful applications, to the particularconstructions which, for the purpose of ex lanation, have been made thesubject of i1 ustration.

In said drawings Figure 1 is a plan view, partially diagrammatic incharacter, of a portion or" a calculating machine embodying the presentinvention, and illustrating only such parts of the machine as arenecessary to an understanding of the invention. 7

Fig. 2 is a transverse vertical sectional view on line 22 of Fig. 1.

Referring to the drawin 1, 1, indicates portions of the calcu atingmachine frame having rotatably journaled therein the usual longitudinalshaft-2 of the setting wheels and dlsks. The latter are indicated by thenumeral 3 and as the same may be of usual or preferred construction,they have not been illustrated in detail. The longitudinally shiftablecarriage is indicated at 4, and between the frame portions 5 thereof isj ournaled the shaft or zero a'xle 6 carrying the numeral wheels 7 ofthe registering mechanism. The wheels 7 may also be of the usual orpreferred type and as the same do not constitute a part of the presentimprovements, only one registering wheel has beenillustrated. The teethof the setting wheels or disks are preferably designed to engageintermediate gear wheels on the usual intermediate longitudinal shaft(not shown), and the intermediate gear wheels are designed to impartrotary movement to the gear wheels of the registering numeral wheels onthe zero shaft 6 when the operating crank on shaft 2 is rotated. Theregistering wheels 7 are loosely mounted on the shaft 6 and the latteris provided with a suitable number of pins, one for each wheel, whichare designed'to contact with suitable projections onthe wheels andthereby rotate the latter when the shaft 6 is rotated.

As is well known in the art, the pins on the shaft 6 are arranged tocontact with and move the registering numeral wheels in such manner thata single rotation of the shaft 6 will bring all of the registeringwheels into alignment at zero, and this is the usual practice prior toeach calculating operation, the shaft 6 being designed to he manuallyrotated by means of the crank handles 8, one preferably secured to eachend of the shaft on the outside of the carriage frame.

The shaft 2 carrying the setting wheels and disks, is designed to berotated in the usualmanner in the performance of the calculatingoperations, by means of the crank handle 9 journaled in the machineframe 1, and carrying on its inner end a gear wheel 10, the lattermeshing with and adapted to rotate a gear wheel 11 on the shaft 2. Thecrank handle .9 is provided with the usual spring pressed operating knob12 adapted to yieldably engage a lug 18 of the handle with a recess 1ain the frame at each rotation of the crank handle, and to yieldably lockthe handle in normal position, as is usual ractice in machines of thischaracter.

In t e operation of the machine the setting disks controlling thesetting wheels on the shaft 2, are adjusted to the desired position, thecarriage 4: is longitudinally shifted to the desired position, and therotation of the crank handle 9 rotates the shaft 2, and the values ofthe calculations are transmitted from the gear wheels of the settingwheels through the intermediate gear wheels described to the registeringor numeral wheels on the shaft 6, in a manner well known in the art. Inorder to insure against the manipulation of the crank handle 9 when thesetting wheels 3 and carriage 4 are in an incorrect position, withconsequent possible injury to the machine;

and in order to insure against, the perform ance of calculations beforethe registering wheels 7 on the shaft 6 have been cleared or reset atzero "through the single rotation of one or both of the clearing handles8, the present invention contemplates a novel and efiicient andpositively operating locking mechanism between the zero shaft 6 and thesetting mechanism shaft 2, which locking mechanism will now bedescribed.

A pair of disks or cams 15 are rigidly secured on the registering wheelshaft (3, and are preferably formed integrally with or as a part of theclearing handles 8 at each end of said shaft. Each of the disks 15 isprovided witha suitably disposed peripheral notch or recess 16. Therecesses 16 in the disks 15 are designed to be engaged by a pair oflevers or lug members 17 rigidly secured on the opposite ends of alongitudinally disposed rock shaft 18, the

latter being pivotally mounted in the frame 1 of the machineintermediate the shafts 2 and 6. The arrangement is such that the lugs17 are engaged by the recesses 16 in the disks 15 when the numeralwheels of the regiflering mechanism on the shaft 6 are in alignment intheir cleared or zeroposition. An intermediate lever 01 lug member 19 isrigidly secured to the rock shaft 18, and is designed to engage at itsfree end the longitudinal portion 20 of a bifurcated lever orU-shapedmember 21 which is pivotally mounted at its inner ends on alongitudinal shaft or support 22 suitably mounted or journaled at itsends in the frame 1 of the machine. The pivoted lever or U- shapedmember 21 is provided on its outer or longitudinal portion 20 with an up-wardly extending lug or projection 23,

which latter is adapted to, be moved into locking engagement with anotch or recess 24 on'the periphery of a locking disk or wheel 25rigidly secured at or near one end of the shaft 2. The arrangement issuch that the lug 23 is in alignment with to engage the recess 24 ofthe' disk 25 when the shaft 2 and setting wheels carried thereby are innormal position, i. e., when the lug 13 of the crank handle 9 is inspring-pressed.

engagement with the recess 14 in the frame 1.

It will be apparent that the arrangement of the locking devicesdescribed is such that in normal position of the machine, and when theregistering wheels are in their cleared or zero position, the lugs 17are held in engagement with the peripheral recesses l6iof the disks 15by the weight pf the pivoted U- shaped member 21 resting upon the outerend of the member 19, and in this position the upwardly p1 ejecting lug23 is out of engagement with the recess 24 and out of the pathof travelof the locking disk 25. In such disengaged position of the lockingdevices, the shaft 2 carrying the setting wheels is freely rotatable bythe crank handle 9 to transmit the values of the desired calculations tothe registering wheels on the shaft 6. During operative positions of themachine the lugs 17 are forced out of the recesses 16 by the turning ofthe clearing handles 8, and the consequent downward movement of the lugs17 rocks the shaft 18 in its bearings and the upward movement of themember 19 lifts the projection or lug 23 of the pivoted lever 21 intolocking engagement with the peripheral recess or notch 24 in the lockingdisk 25. I will be apparent that in this latter locked or engagedposition of the mechanism, the rotation of the shaft 2 and settingwheels carried thereby is effectually prevented when the clearinghandles 8 have been rotated out of their normal position, damage to themachine is thereby obviated, and the setting disks are locked in theiradjusted position during the performance of calculations through themanipulation of the clearing handles ,8.

It will be further apparent that through the engagement of the lockingdevices described, errors in the values of the calculations areautomatically prevented for the reason that the crank handle 9 cannot berotated until the numeral wheels of the registering mechanism have beencleared or returned to zero by the single rotation of the clearinghandles 8. In the absence of a looking mechanism of the characterdescribed, frequent errors in calculations result through the omissionof the operator to return the registering wheels to zero at theconclusion of a calculating operation, the manipulation of the crankhandle 9 after new settings have been performed on the setting disksbefore the registering wheels have been cleared, resulting obviously inincorrect values on these latter wheels.

When the clearing handles 8 are given a single rotation to clear theregistering wheels 7 on the shaft 6, the lugs 17 drop into engagementwith the recesses 16 in the disks 15, the projection 23 drops out of therecess 24 and out of the path of the locking disks 25, and the shaft 2carrying the setting mechanism is again freely rotatable for theperformance of subsequent calculations.

In this connection it will be observed that the peripheral notch 2a indisk 25 is provided with inclined faces as illustrated. This peculiarconstruction of the notch 24 tends to force the correspondingly inclinedprojection 23 of U-shaped locking bar 21 out of engagement with saidnotch when the operating crank is rotated in either direction. Thisaction occurs provided the zero setting mechanism carried by shaft 5 isin or being moved to normal zero position. The described inclinedconstruction and cooperation between notch 24 and projection 23facilitates the operation of the machine when starting, stopping orshifting.

From the foregoing it will be apparent that the provision of theimproved locking devices described, results in efficient, positive andautomatic means whereby'undue damage to the machine during operationthereof is prevented, and errors in the values of the calculations,resulting from the inadvertent omission to clear the registeringmechanism at the conclusion of a prior, calculation, are alsoautomtically and effectually prevented.

What is claimed is:

1. In a ealculatingmachine, in combination with a setting mechanism anda registering mechanism: a handle secured to the shaft of saidregistering mechanism and having a peripheral notch, a rock shaftpivotally mounted adjacent said registering mechanism, a lug secured tosaid rock shaft and normally on aging said peripheral notch in said hande, a lever secured to said rock shaft and adapted to engage a U-shapedlever pivotally mounted in said machine to move the latter intoengagement with a peripheral notchformed in a disk of said settingmechanism, the aforesaid engagement being effected when said lug ismoved out of engagement with the peripheral notch of said registeringmechanism handle, whereby the setting mechanism is locked in normalposition when said registering mechanism is in abnormal position, andvice versa.

2. In a calculating machine in combination with a setting mechanism anda registering mechanism: separate locking levers each pivotally mountedadjacent to and adapted to engage one of said mechanisms, said levershaving engagement with one another, whereby both of said mechanisms areunlocked when they are in normal cleared, position, said settingmechanism is locked against movement when said registering mechanism isin abnormal position, and said registering mechanism is locked againstmovement when said setting mech: anism is in abnormal position.

3. In a calculating machine, in combination with a setting mechanism anda registering mechanism: a disk secured to the shaft of said registeringmechanism and having a eri heral recess, a disk secured to the sha t ofsaid setting mechanism and having a peripheral notch, a rock shaftpivotally mounted adjacent said registerin mechanlsm, a lug secured tosaid rock shaft and normal] engaging said peripheral recess in sai diskwhen said registering mechanism is in zero position, a lever secured tosaid rock shaft, a shaft mounted in said machine adjacent said, settingmechanism, a,lcvcr pivoted on said latter shaft and adapted to be movedinto engagement with said peripheral notch of said disk by said leveronsaid. rock shaft when said lug has been moved out of engagement withsaid peripheral recess of said registering mechanism, whereby saidsetting mechanism is locked in adjusted position when said registeringmechanism is in abnormal position, said lever engaging said peripheralnotch being designed to contact with said lever on said rock shaft toautomatically move said lug into engagement with said peripheral recesswhen the setting mechanism has been returned to normal position, saidmovement releasing the pivoted lever adjacent said setting mechanismfrom engagement with said locking disk to permit the actuation of saidsetting mechanism.

4. In a. calculating machine, in combination with setting mechanism andregistering mechanism and rotatable shafts therefor: a rock shaftpivotally mounted intermediate said setting mechanism, a lever securedto said rock shaft a disk mounted on said setting mechanism shaft andhaving a locking recess, a disk mounted on said registering mechanismshaft and having a peripheral recess, a pivoted lever operativelyengaged at its free end by said first mentioned lever and having a lugadapted to be moved by the latter into locking engagement with saidlocking recess, and an arm mounted on said rock shaft and adapted to berocked into engagement with said peripheral recess, whereby the rotationof said registering mechanism shaft moves said peripheral re- "cess outof engagement with said arm and rocks said rock shaft to engage saidfirst mentioned lever with said lug on said pivoted lever and move thesame into locking engagement with said locking recess on said settingmechanism disk to prevent rotation of said setting mechanism shaft.

lin testimony whereof lt affix my signature.

@TTQ lP. SCHUMAN.

